Why does the air conditioner on my 2003 nissan altima only work on position 4?

SOURCE: 2003 Nissan Altima 2.5S, Check Engine Light Problem.

this problem could be caused by the mass air flow censor, i had the same problem with my car. it is really pricey at the dealer so you might want to check elsewhere for this part. I found one at a scrap yard for 85% less that the dealer and i also got life time warranty, the dealer does not offer any warranty on this part.

Paul W

• 404 Answers
• Posted on Feb 24, 2009

SOURCE: Nissan Altima no cool air blowing or hot air blowing

Hi!
It appears we have an Air lock scenario and you will need to perform a system Bleed.
Park the vehicle on level ground, when cold remove coolant filler cap, start engine and leave to idle, turn heater on full and blower to max. When engine reaches operating temperature watch and listen near coolant filler, keep clear as gurgling and hopefully a boil over should occur. Top up with very warm coolant and wait as it may do it again.
Check for heat inside vehicle if warm replace coolant cap but keep an eye on temperature gauge as the ~Air lock may have moved on from heater matrix/core so proceedure needs to be carried out again from COLD.

Please press the Blue button to appraise my FREE Efforts, Thank You!
Paul 'W' U.K

SOURCE: CRANK SHAFT POSITION SENSOR 20002 NISSAN ALTIMA

1st, Nissan had a recall on Crank position sensors for 2002-2006 Altima's. Check with you dealer before you go doing any repairs. You may discover you can get your car repaired at no charge.
NHTSA Campaign ID number :O7V527000
Symptom: Erratic behavior. Stalling and no starts and very difficult to diagnose due to the time frame in which the component actually malfunctions. The warranty should not be limited to the original owner.
I would also need more specifics as to which engine you have so I might assist you in where the location of the sensor is. The Altima had a 4 and a 6 cyl engine offered that year.

SOURCE: The camshaft position sensor has

JUST REPLACE IT IN THE SAME POSITION THAT IT CAM FROM

SOURCE: Crank position sensor for 2003 Nissan Altima

a crank position sensor , sends a signal to pcm about crankshaft position signal, the sensor controls spark timing and firing order. the signal is also used for pcm to detect a missfire!! it also sends this info to ignition module, any mechanic can replace a crankshaft sensor!! call a auto parts store and see if you can get one, the cost should be a lot less.